Field
Apparatuses and methods consistent with the present disclosure relate to a touch screen apparatus and a control method thereof, and more particularly, to an ultrasonic touch screen apparatus and a control method thereof.
Description of the Related Art
A touch sensing apparatus, such as a touch screen, a touchpad, or the like, is an input device that is attached to a display apparatus to provide an intuitive input method to a user. The touch sensing apparatus has been widely applied to various types of electronic devices such as a portable phone, a personal digital assistant (PDA), a navigation system, etc. In particular, as demands for smartphones have increased, a ratio of using a touch screen as a touch sensing apparatus capable of providing various input methods in a limited form factor has also increased.
A touch screen applied to a portable device may be realized as a resistive type, a capacitive type, an infrared (IR) type, a surface acoustic wave (SAW) type, etc. according to methods of sensing touch inputs.
As compared to a resistive type, capacitive type, etc. screen, in SAW type touch screen, irradiated ultrasonic waves meet an obstacle, and thus sizes of waves are reduced. Since the SAW type touch screen has a high light penetrability, and high accuracy and definition, the SAW type touch screen has been widely applied mainly to an unmanned information terminal, etc.
However, there are disadvantages to a SAW type touch screen. A related art SAW type touch screen is vulnerable to pollutants on a touch screen surface, and ultrasonic waves are irradiated along the touch screen surface. Therefore, the related art SAW type touch screen has a low recognition performance of a soft touch. Also, the related art SAW type touch screen needs a plurality of acoustic reverberators and additional processing for preventing a ghost touch. Therefore, a design of the related art SAW type touch screen is complicated, and the cost thereof increases.
Therefore, it would be advantageous to have methods of further conveniently increasing a recognition performance of a touch at a low cost.